#include <stdio.h>
#include <string.h>

struct user
{
    int id;
    char name[20];
    struct user *next;
};

/*int main()
{
    struct user a, b, c, *head;
    a.id = 1;
    strcpy(a.name, "tom");
    b.id = 2;
    strcpy(b.name, "jackson");
    c.id = 3;
    strcpy(c.name, "churchill");
    head = &a;
    a.next = &b;
    b.next = &c;
    c.next = NULL;

    struct user *u;
    u = head;
    while (u != NULL)
    {
        printf("%d,%s\n", u -> id, u -> name);
        u = u -> next;
    }
    return 0;
};*/
